In a speech from Fort Myers, Fla., President Obama said today was "a day for prayer and reflection."

The President cancelled a planned campaign event and instead addressed the mass shooting at a movie theater in Aurora, Colo. He asked those gathered to pause for a moment of silence to remember the victims.

"Even as we learn how this happened and who's responsible, we may never understand what leads anyone to terrorize their fellow human beings like this," Obama said. "Such violence, such evil is senseless; it's beyond reason."

And while we may never understand why something like this happens, what we know, he said, is "what makes life worth living."

"The people we lost in Aurora, loved and they were loved. They were mothers and fathers, they were husbands and wives, sisters and brothers, sons and daughters, friends and neighbors. They had hope for the future ... and dreams that were not yet fulfilled," Obama said.

What we can take of this, Obama said, is "the reminder that life is very fragile."

"What matters at the end of the day is not the small things, it's not the trivial things, which so often consume us in our daily lives. Ultimately it's how we choose to treat one another and how we love one another," Obama said.

The president said when he heard the news he thought about his daughters.

"My daughters go to the movies," he said. "What if Malia and Sasha had been at the movies?"

The president said the country was "heartbroken" over the tragedy. He said the federal government would take whatever steps were necessary to protect Americans and they would stand with the city of Aurora.

But Obama said that tonight, he would hug his children "a little tighter."